3.1 NAS 1 - Fire Fighting Training Pit
Addressing speculation about contamination.
The stated objective of the EQS is "to address persistent speculation in the media that parts of Subic Bay are seriously contaminated with toxic wastes generated by the former US Navy activities and operations." The source of media speculation is stated to be two reports: (1) "Subic Bay Environmental Risk Assessment and Investigation Program," the World Health Organization Mission Report and (2) "Environmental and Health Impact Report on Known and Potentially Contaminated Sites at Former US Military Bases in the Philippines," prepared by member of the 1994 Positive Legacy Tour.
Sludge Pit/Old Dump Site was not located.
Site reconnaissance failed to identify an old dump site reported at this location by the US Navy. It is unclear whether the dump site area indicated by the Navy on a map was sampled during the site investigation.
Status of underground storage tank
An underground storage tank was suspected at a location adjacent to the smoke house. It is not stated what the tank stored, whether the tank currently contained product and if the tank was reported to be leaking when it was taken out of service. The location of the groundwater monitoring well in relationship to the underground storage tank is not shown on the "not to scale" map. The distance of the monitoring well from the underground tank may not be close enough to determine if the tank had leaked. Soil sampling was not performed at a sufficient depth to determine a tank leak.
Rationale for monitoring well location.
No explanation is given for the location of MW-1. Based on discussions of regional groundwater flow (Vol. 1, p. 3-2) being in a westerly direction and the assumed surface gradient indicated by drainage also being towards the west, it would appear MW-1 is located upgradient or cross gradient from suspected source areas (underground storage tank, burn pit, and the debris disposal area).
No explanation for distribution of contaminants.
No explanation is made to explain the high levels of PCBs (8.13 mg/kg) that are present in a soil sample from MW-1. No attempt is made to determine the areal extent or depth of this contaminant or any other contaminant identified at the site.
Construction debris was located 0.3 miles from Fire Station.
Construction debris, a potential asbestos containing material was dumped in an area located 0.3 miles from the Fire Station. This environmental concern was not addressed by the EQS.
Migration Potential
Site 1 is located in close proximity to Site 16 and Site 17. The potential for contaminants to migrate from Site 1 to these presumably down-gradient sites was not evaluated.
Failure to sample test pit.
A test pit was dug in an area where water would collect during the rainy season. This pit was not sampled because "contamination was not observed." Observations may fail to identify the presence of contaminants, even when these contaminants are present at sufficient concentrations to cause human health impacts.
Volatile Organic results in soils are inconclusive.
Only surface soil samples were collected from this site.
Potential contaminant not included in soil sample analysis.
Dioxins were identified by the EQS as a potential contaminant at Site 1. No sampling for dioxins was performed. Given the high levels of PCBs detected in soils at the site a high potential exists that dioxins would be found as well. Site 1 should be sampled for the presence of dioxins.
The recommendations do not address the contamination at the site.
The EQS recommends the removal of small quantities of ash from this site. A total of 500 to 1,000 cubic meters. This material would be stabilized and disposed of in the existing landfill (Site 45) at a cost of $5,000 to $16,000 US dollars.
However, following the removal action Site 1 would still contain Total Petroleum Hydrocarbons (TPH), polychlorinated biphenyls, arsenic, lead, zinc, and four polynuclear aromatic hydrocarbons (PAHs) in excess of screening levels. Further investigation and remediation work would be required at this site. The EQS therefore underestimates the cost required to address contamination at this site.
Current use of site may be contributing to further environmental degradation.
Proper environmental controls should be established at the site if fire-fighting training is to continue in this location.
3.2 NAS 2 Crash Crew Training Tank
Significant enough levels of petroleum hydrocarbons are present to warrant an investigation of groundwater impacts.
Significant levels of petroleum hydrocarbons were found in the three soil samples from the site. One sample location contained TPH at a concentration of 11,875 mg/kg. Investigation of groundwater at Site 2 is warranted based on the potential for soil contamination to impact groundwater quality.
Potential for contaminant migration from nearby toxic sites.
Groundwater sampling performed at the nearby High Speed Refueling area shows that groundwater in this area is significantly contaminated by petroleum hydrocarbons. A potential exists that petroleum releases from the High Speed Fueling Area may impact Site 2 groundwater.
Volatile Organic results in soils are inconclusive.
Only surface soil samples were collected from this site.
No rationale for soil sample locations.
Soil samples were collected from locations on three sides of the tank to evaluated impacts of a tank overflow. No sample was collected from the fourth side.
Potential for off-site impacts not investigated.
It is also reported that the tank was drained to a nearby creek and bay. The drainage of fire-fighting water likely contaminated the drainage area with unburned hydrocarbons and products of combustion. These off-site impacts were not investigated during the EQS.
Potential contaminant not included in soil sample analysis.
Dioxins were identified by the EQS as a potential contaminant at Site 2. No sampling for dioxins was however performed. Site 2 should be sampled for the presence of dioxins.
Soil contamination needs to be addressed.
No recommendations for further action were made for Site 2 despite the findings that TPH exceeded the soil screening level by a factor of 10.
3.3 NAS 3 Washrack Holding Tank, Structure 8415
Site History is limited.
The history of Site 3 begins in 1981. No further information on the use of hazardous materials at the site is provided. Of equal interest is how aircraft were cleaned prior to the construction of the holding tank at Site 3.
Washrack chemical results.
The EQS identified information on contaminants found in water samples from a washrack holding tank. The EQS sample analysis did not included a number of chemicals (ethylene glycol for example) found in the holding tank.
Potential for contaminant migration from nearby toxic sites.
Groundwater sampling performed at the nearby High Speed Refueling area shows that groundwater in this area is significantly contaminated by petroleum hydrocarbons. The potential exists for petroleum contaminated groundwater from the High Speed Fueling Area to impact Site 3 groundwater. The EQS did not evaluate contamination migration.
Volatile Organic results in soils are inconclusive.
Only surface soil samples were collected from this site.
Surface soil samples are inconclusive
The shallow sample depths would detect impacts from tank overflows only. The samples were not deep enough to detect a leak from the base of the tank which is at a depth of 10 feet below ground surface. Information on the depth of lines that drain to tank are not given in the EQS, but it is likely that the shallow soil samples were above any release point from these buried lines.
Rationale for soil sample locations not provided.
Soil samples were collected from three sides of the tank to evaluated impacts of a tank overflow. No sample was collected from the fourth side.
Potential for petroleum hydrocarbons in groundwater should be investigated.
Groundwater contamination was identified near the other Washrack Holding Tank, Site 4. It is reasonable to expect that similar groundwater contamination would exist at Site 3.
Extent of PAHs in soil should be fully investigated.
PAHs levels in soils exceeded screening limits but no additional remedial work was recommended.
Rejecting validated data.
The soil sample data showing high levels of PAHs, having been validated by EPA procedures, was rejected on the assumption of "sample contamination" by asphalt.
3.4 NAS 4 Washrack Holding Tank, Structure 8416
Site History is limited.
The history of Site 4 begins in 1980. No further information on the use of hazardous materials at the site is provided. Of equal interest is how aircraft were cleaned prior to the construction of the washrack holding tank at Site 4.
Washrack chemical results.
The EQS identified information on contaminants found in water samples from a washrack holding tank. The EQS sample analysis did not included a number of chemicals (ethylene glycol for example) found in the holding tank.
Volatile Organic results in soils are inconclusive.
Only surface soil samples were collected from this site.
Depths of soil samples.
The sample depths would address impacts from tank overflows only. The samples were not deep enough to detect a leak from the base of the tank which is at a depth of 10 feet below ground surface.
Rationale for soil sample locations.
Three samples were collected in close proximity at one end of the washrack tank and one sample from the opposite end of the tank. No samples were collected between the drainage canal and tank. Overland flow directly to the canal would appear to be to most likely path in the event of a tank overflow.
Extent of petroleum hydrocarbons in groundwater should be fully investigated.
Groundwater screening levels for TPH were not exceeded in the single groundwater sample collected from Site 4. However, the source of petroleum hydrocarbons in groundwater is not defined. Therefore, further investigation is needed to determine the magnitude and the lateral extent of groundwater contamination.
3.5 NAS 5 Boat Shop - Building 8122
Historical Information not provided.
All historical information provided by the EQS could be determined from the name of the facility. In light of the lack of historical information an inadequate level of sampling was performed.
Potential for contaminant migration from nearby sites.
The potential for contaminant migration from nearby sites was not considered. Site 5 is located downgradient or adjacent to Site 6, Site 8, and Site 9.
No rationale for sample locations.
Sample locations were to target specific areas of suspected contamination or in areas where wide-spread contamination was anticipated, sample locations were to be randomly chosen along a grid pattern. The sample locations at Site 5 do not appear to follow either sampling strategy.
Volatile Organic results in soils are inconclusive.
Only surface soil samples were collected from this site.
PAH contamination needs to be further evaluated.
This site was not recommended for further investigation or remedial action. Four PAHs were found in samples above their soil screening limits. The depth and lateral extent of PAH contamination at Site 5 needs to be further investigated.
3.6 NAS 6 Boton Wharf PWC Vehicle Maintenance Yard
Potential for contaminant migration from nearby sites.
The potential for contaminant migration from nearby sites was not considered. Site 6 is located downgradient or adjacent to Site 5, Site 7, Site 8, and Site 24.
Volatile Organic results in soils are inconclusive.
Only surface soil samples were collected from this site.
Potential to over-look hot-spot.
A sample grid of 50 meters x 24 meters was used throughout the center of the site. This sampling density indicates that there is a 10 percent chance of over-looking a contaminated "hot-spot" with an area of 50 meters by 24 meters.
Locations of samples not provided.
Relationship of SS07 and MW-1 to known landmarks are not provided on the "not to scale" Figure 6.1. Location of MW-2 is not shown on Figure 6.1.
Results of groundwater sampling for MW-2 have not been reported in the EQS and it appears that this well was not installed. A soil sample was, however, collected from the MW-2 boring at a depth of 1.4 meters and contained 739 mg/kg of TPH in the C15 to C28 range.
Underground Storage Tank status.
No information on the integrity of underground tanks at Site 6 is provided. The sampling performed at the site may not be adequate to evaluate a leak from these tanks. Soil samples were too shallow and the distance between the underground tanks and MW-1 is uncertain.
Groundwater needs to be fully evaluated.
Petroleum and lead exceeded groundwater screening levels in samples from MW-1. Despite this, no further investigation or remedial action was recommended for Site 6. Further groundwater characterization is needed to define the contaminant source(s), the lateral extent and magnitude of contamination.
3.7 NAS7 Construction Battalion Vehicle Maintenance Yard
Historical Information not provided.
All historical information provided by the EQS could be determined from the name of the facility. In light of the lack of historical information an inadequate level of sampling was performed.
Potential for contaminant migration from nearby sites.
The potential for contaminant migration from nearby sites was not considered. Site 7 is located downgradient or adjacent to Site 6, and Site 24.
Potential to overlook hot-spot.
Samples do not appear to target any activity. The only source area identified is a outdoor storage area of motor oil, engine coolant, and oily gravel. Samples were spaced on 55-meter by 45-meter grid pattern. This sampling density indicates that their is a 10 percent chance of over-looking a contaminated "hot-spot" with an area of 55 meters by 45 meters.
Volatile Organic results in soils are inconclusive.
Only surface soil samples were collected from this site.
Further investigation of petroleum hydrocarbons in soil is necessary.
Levels of TPH above the screening level were found at Site 7. Despite these findings, no further investigation or remedial action was recommended by the EQS. Based on soil sample results, the potential for groundwater contamination needs to be investigated at this site.
3.8 NAS 8 Jet Engine Maintenance and Testing Facility
No site history is provided.
The EQS does not provide specific information on the site history such as the construction dates of buildings and facilities. The EQS does not provide information on hazardous material use, and suspected source areas. Given the lack of historical information, an inadequate level of sampling was performed at Site 8 during the EQS.
Potential for contaminant migration from nearby sites.
The potential for contaminant migration from nearby sites was not considered. Site 6 is located downgradient or adjacent to Site 5, Site 6, and Site 9.
Volatile Organic results in soils are inconclusive.
Only surface soil samples were collected from this site.
No information on status of underground tanks.
Underground tanks are located at the site. No information on leaks, inventory records or other monitoring information for these tanks are reported in the EQS. No sampling specifically targets the underground tanks to determine if a leak had occurred.
Monitoring well locations are inappropriate.
The inferred groundwater flow direction is to the west. Neither MW-1 nor MW-2 would intercept plumes originating from an underground storage tank or buried fuel pipeline location. The petroleum levels measured in groundwater are likely not characteristic of the highest levels found at Site 8. The locations of wells on the "not-to-scale" figures have not been related to landmarks.
Out-of-service transformers not investigated.
A sample collected near a transformer location was not analyzed for PCBs.
Site recommended for further unspecified action.
TPH, arsenic and lead are found at Site 8 above soil screening levels. Site 8 was recommended for further action only if a change in property use occurs. No further investigation or remedial action was specified. Given the level of contaminants in soil a groundwater investigation is warranted for Site 8.
3.9 NAS 9 General Industrial Area East of Boton Wharf
Volatile organic results in soils are inconclusive.
Only shallow soil samples were collected from this site.
Potential for contaminant migration from nearby sites.
The potential for contaminant migration from nearby sites was not considered. Site 9 is located downgradient or adjacent to Site 5, and Site 8.
Deposition of hazardous air pollutants from incinerator not evaluated.
The description of Site 9 indicates that an incinerator, including underground fuel storage tanks, is located adjacent to the photo processing facility at the site. Potential deposition of pollutants from the stack of the incinerator should be evaluated. These pollutant may have impacts away from Site 9 in the prevalent down wind direction(s).
Location of gas station not indicated on site plan.
A former gas station is stated to be located at Building 8112. Building 8112 is not shown on Figure 9.1, the Site 9 plan. According to the EQS text the investigation at Site 9 centered around the gas station. Figure 9.1, however, shows the investigation centered around Building 8121, Flammable Material Storage and Building 8167, Photo Processing Plant.
Monitoring well location.
The use of "not to scale" maps required sample locations to be related to known landmarks. The location of MW-1 on Figure 9.1 is not related to known landmarks. The distance of MW-1 to the suspected source of contaminants is not provided.
Result tables disagree.
Table 9.1.2 indicated that sample SS03 was to be reanalyzed. This sample was not reanalyzed during the confirmation round. No explanation was provided for not repeating sampling in this location.
Groundwater investigation is incomplete.
A necessary next step to complete evaluation of Site 9 is to determine the lateral extent and magnitude of groundwater contamination through installation of monitoring wells and the determination of groundwater gradients, flow direction, and tidal influence.
Site 9 recommended for further unspecified action.
Petroleum hydrocarbons exceed screening levels in soils and groundwater at Site 9. No further investigation or remedial action was specified.
